Bleaching process and compositions therefor

ABSTRACT

A PROCESS FOR ACTIVATION OF PEROXYGEN BLEACHING AGENTS WHICH COMPRISES CONJOINTLY DISSOLVING IN AQUEOUS SOLUTION CERTAIN PROXYGEN BLEACHING AGENTS, CERTAIN ALDEHYDE OR KETONE BLEACH ACTIVATORS, AND BUFFERING COMPOUNDS, CONCENTRATED DRY BLLACH COMPOSITIONS CONTAINING A PEROXYGEN COMPOUND; AN ALDEHYDE- OR KETONE-PRODUCING ACITIVATOR AND A BUFFERING AGENT AS ESSENTIAL INGREDIENTS ARE ALSO DISCLOSED.

United States Patent O 3,822,114 BLEACHING PROCESS AND COMPOSITIONS THEREFOR Ronald E. Montgomery, Cincinnati, Ohio, assignor to The Procter & Gamble Company, Cincinnati, Oh1o No Drawing. Continuation-impart of abandoned application Ser. No. 169,491, Aug. 5, 1971. This application Sept. 28, 1972, Ser. No. 293,262 Claims priority, application Great Britain, Aug. 1, 1972, 35,878/72. Int. Cl. D061 3/02 U.S. Cl. 8-111 34 Claims ABSTRACT OF THE DISCLOSURE A process for activation of peroxygen bleaching agents which comprises conjointly dissolving in aqueous solution certain peroxygen bleaching agents, certain aldehyde or ketone bleach activators, and buffering compounds. Concentrated dry bleach compositions containing a peroxygen compound; an aldehydeor ketone-producing activator and a buffering agent as essential ingredients are also disclosed.

CROSS-REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of the application of Ronald E. Montgomery entitled Bleaching Process and Compositions Therefor, having Ser. No. 169,491, filed Aug. 5, 1971, and now abandoned.

BACKGROUND OF THE INVENTION This invention relates to an improved process for activating peroxygen bleaching agents. In addition, it relates to bleaching compositions in concentrated form which alone or in combination with other ingredients can be added to water to effect the bleaching process of the instant invention.

The invention employs as essential ingredients a combination of a peroxygen bleaching compound, an aldehyde or ketone compound as a bleach activator and a buffering agent.

Bleaching processes and compositions can be used in several ways to solve cleaning and laundering problems encountered in the home.

Bleaching systems are, of course, utilized in the home for direct bleaching of stains on fabrics and hard surfaces. Commonly encountered hypochlorite bleaches are effective at stain-removal when used in relatively high concentrations, but these hypochlorite, as well as other active chlorine bleaches, cause rather severe damage to fabric colors and can in addition damage textile fibers with repeated use. Liquid bleaches of this type also present handling and packaging problems. While color and fabric I damage may be minimized by employing milder oxygen bleaches such as potassium monopersulfate, stain removal characteristics of these peroxygen bleaches are much less desirable than those of the harsh halogen bleaching agents. Therefore, commercial bleaching compositions containing peroxygen bleaches occasionally utilize activators, i.e., compounds which enhance peroxygen bleaching performance. Prior art bleaching compositions have employed various types of such activator compounds including esters, carboxylic acid anhydrides, quaternary ammonium salts and carboxylic acid salts among others. (See Popkin, U.S. Pat. 1,940,768, Dec. 26, 1933; Baevsky, U.S. Pat. 3,061,- 550, Oct. 30, 1962; MacKellar et al., U.S. Pat. 3,338,839, Aug. 29, 1967; Woods, U.S. Pat. 3,532,634, Oct. 6, 1970; Stalter, U.S. Pat. 3,556,711, Ian. 19, 1971; and the copending applications of John Paul Jones and Charles H. Nicol, Ser. Nos. 117,590 and 117,814, both filed Feb. 22,

1971.) While certain of these activators have been found effective, there is a continuing need for effective activators other than those presently employed in the art so that better fabric and hard surface bleaching can be obtained with these solid peroxygen bleaching compounds.

Bleaching systems find utilization in the home in areas other than that of direct bleaching of stained material. A bleaching system can, for example, be employed to combat one of the most persistent and troublesome problems arising during modern fabric laundering operations the tendency of some colored fabrics to release into laundering solutions dye which is then transferred during laundering onto other fabrics being washed therewith. Heretofore, there has been no good way to combat the problem of dye transfer other than by mechanically sorting the fabrics to partition said fabrics into dark and light shades for separate laundering.

Suspended or solubilized dyes of all types can to some degree be oxidized in laundering solution by employing known chlorine, peroxygen, activated peroxygen or peroxygen-chlorine bleaching compositions in high concentrations. While such bleaches inhibit dye transfer, they also damage dyes on fabrics thereby making their use for laundering of colored fabrics undesirable. Some of the milder peroxygen and activated peroxygen bleaching formulations can be utilized during laundering of colored fabrics with minimal color damage. (Examples of such compositions include the above-described micelle-catalyzed peroxygen bleaching composition disclosed in the copending U.S. Patent Applications of John Paul Jones having Ser. Nos. 117,590 now U.S. Pat. No. 3,739,673; and 117,814 now U.S. Pat. No. 3,749,674, both filed Feb. 22, 1971.) While compositions of this type are effective to some extent for the inhibition of transfer of certain solubilized or suspended dyes, overall dye transfer reduction is of minimal significance.

In light of the foregoing considerations concerning direct bleaching and dye transfer in laundering, it is an object of the instant invention to provide improved methods for enhancing peroxygen bleaching activity to provide useful peroxygen bleaching systems.

It is a further object of the present invention to provide improved concentrated bleaching compositions for use alone or in conjunction with other conventional laundering materials to enhance removal of stains on fabrics.

It is a further object of the present invention to provide improved concentrated bleaching compositions for use alone or in conjunction with other conventional hard surface cleaning materials to enhance removal of stains on hard surfaces.

It is a further object of the present invention to provide concentrated bleach-containing compositions which can be added to fabric laundering solutions to eliminate or reduce the transfer of solubilized or suspended dye from one fabric to another during washing.

It is a further object. of the present invention to provide concentrated dye transfer inhibition compositions which are compatible with and in fact can be made a part of conventional surfactant-containing fabric laundering detergent compositions.

It has now been discovered that by combining certain aldehyde or ketone compounds with certain peroxygen bleaching agents and a buffering agent, improved processes and compositions result which accomplish the above-described objectives and which are unexpectedly superior to bleaching processes and compositions of the prior art.

SUMMARY OF THE INVENTION This invention provides an improved peroxygen bleach activation process comprising conjoint dissolution in aquewherein R is selected from the group consisting of alkylene groups containing from 1 to about 16 carbon atoms and arylene groups containing from 6 to about 8 carbon atoms and Y is hydrogen, halogen, alkyl, aryl or a group providing an anionic moiety in aqueous solution; or (4) a mixture of such bleaching compounds; (B) an aldehyde or ketone activator compound providing a Relative Oxidation Constant of 0.25 or greater; and (C) a buffering agent capable of maintaining the pH of said aqueous solution within the range of about 7 to 12.

Concentrated compositions comprising materials which yield these three components upon dissolution in water are also provided. Such compositions can be employed to carry out the instant bleach activation process for the purpose of bleaching stains on fabrics and hard surfaces and for reducing dye transfer in conventional laundering solutions.

DETAILED DESCRIPTION OF THE INVENTION The instant invention relates to a process for activating peroxygen bleaching and to compositions useful for carrying out such a process. The bleach activation process is, of course, carried out by conjointly dissolving in aqueous solution, a peroxygen bleaching compound, an activator compound and a buffer. Compounds which provide these three types of materials in solution being the essential components of the bleaching compositions of the instant invention. The peroxygen bleach-activator-buifer combination finds utility in three major practical areas. Such a system can be used alone or in combination with other optional ingredients to effectuate (1) direct bleaching of stains on fabrics; (2) removal by bleaching of stains found on hard surfaces; and (3) inhibition of the transfer to fabric articles of solubilized or suspended dyes found in fabric laundering solutions. The essential peroxygen bleach, activator, and buffer components of the instant invention are discussed in detail followed by a discussion of the use of the instant peroxygen bleach-activator-bulfer combination in each of these three areas:

The Peroxygen Compound The principal bleaching agents utilized in the instant process and composition are inorganic peroxygen salts and organic peroxy acids (and water-soluble salts thereof). Any such salt or acid which in aqueous solution yields a species containing a OO moiety is operable in the present process.

Examples of inorganic peroxygen salts include the water-soluble monopersulfates and Water-soluble monoperoxyphosphates. Specific examples of such salts include sodium monopersulfate, potassium monopersulfate, disodium monoperphosphate and dipotassium monoperphosphate. Highly preferred peroxygen salts, i.e., those which are most highly activated by activators in the practice of the instant invention, are the sodium and potassium monopersulfates of the formulas NaHSO and KI-ISO respectively. Potassium monopersulfate is available commercially from E. I. du Pont de Nemours and Company, Inc. under the trade name Oxone. Oxone contains approximately 41.5% by weight KI-ISO the balance being KHSO and K 80 in about equal proportions.

Operable peroxyacids of the present invention have the general formula wherein R is an alkylene group containing from 1 to about 16 carbon atoms or an arylene group containing from 6 to about 8 carbon atoms and Y is hydrogen, halogen, alkyl, aryl or any group which provides an anionic moiety in aqueous solution. Such Y groups can include, for example,

Thus the organic peroxyacids or salts thereof of the invention can contain either one or two peroxy groups and can be either aliphatic or aromatic. When the organic peroxyacid is aliphatic, the unsubstituted acid has the general formula 0 HOOl J-(CHI)DY where Y, for example, can be and n can be an integer from 1 to 12 with perazelaic acids (n=7) being the preferred compounds. The alkylene linkage and/or Y group (if alkyl) can contain halogen or other non-interfering substituents. Examples of preferred aliphatic peroxyacids include diperazelaic acid and diperadipic acid.

When the organic peroxyacid is aromatic, the unsub stituted acid has the general formula HO-O( JCuH4-Y where Y is hydrogen, halogen, alkyl,

and Y groupings can be in any relative position around the aromatic ring. The ring and/or Y group (if alkyl) can contain any non-interfering substituent such as halogen groups. Examples of suitable aromatic peroxy acids or salts thereof include monoperoxyphthalic acid, diperoxyterephthalic acid, 4-chlorodiperoxyphthalic acid and the monosodium salt of diperoxyterephthalic acid. Preferred aromatic peroxyacids are m-chloroperoxybenzoic acid and p-nitroperoxybenzoic acid. A highly preferred aromatic peroxyacid is diperoxyisophthalic acid. Mixtures of the peroxygen salt compounds and the peroxyacids can be employed in the instant process.

These bleaching agents are, of course, dissolved conjointly with a bleach activator and a buffer in aqueous solutions to carry out the bleach activation process of the instant invention. Generally, the bleaching agent provides from about 2 p.p.m. to 2,000 p.p.m. available oxygen in soluiton. Preferred concentration in bleaching solution, however, depends upon the intended use of the particular activated bleaching system employed. Preferred solution concentrations of the peroxygen compound for various uses of the instant process are provided hereinafter.

In general, peroxygen bleaching agent is present in concentration compositions of the instant invention to the extent of from about 1% to 75% by weight. Again, preferred concentration ranges for the peroxygen bleaching agent in concentrated compositions depend upon the particular utility for which a given composition is prepared. Such preferred embodiments are discussed more fully hereinafter.

It should be noted that peroxygen compounds of the instant invention are limited to certain true persalts and peracids and do not include those common peroxygen bleaching agents which yield hydrogen peroxide in aqueous solution. Compounds of this type (hydrogen and alkali metal peroxides, perborates, percarbonates and persilicates) are not activated by the instant aldehyde and ketone compounds to the extent that true persalts and peracids are so activated. In addition, certain persulfate salts, notably the peroxydisulfates are likewise not useful in the instant invention.

The Activator Component The peroxygen bleaches of the instant invention are activated by certain aldehydes or ketones. An aldehyde is of course any compound which contains at least one carbonyl group and has two hydrogen atoms or a carbon atom and a hydrogen atom attached directly to at least one of the carbonyl carbon atoms. A ketone is any compound which contains at least one carbonyl group and has two carbon atoms attached directly to at least one of the carbonyl carbon atoms. These compounds may be aliphatic or aromatic, substituted or unsubstituted, saturated or unsaturated, or acyclic, carbocyclic or heterocyclic.

Although the scope of the present invention is not limited by any particular theory, aldehyde or ketone activation is believed to occur as follows: The peroxygen bleaches of the instant invention are believed to ionize in solution to form an anionic species having the general formula RO0 wherein R, for example, can be when a monopersulfate compound is used. This species will combine with the aldehyde or ketone activators of the present invention which can have, for example, the acyclic general formula 1 Rr--Rz to form an intermediate of the known Baeyer-Villiger reaction. It is believed that this intermediate species has the general formula It is this species which is thought to greatly enhance the bleaching in the instant invention over peroxygen bleaching alone.

The activated bleaching s'pecies, in addition to oxidizing stain or dye, can decompose. It is thus essential that activators employed in the instant invention have chemical properties which provide bleach activation, i.e., formation of the active bleaching species, and hence stain or dye oxidation at a rate which serves to overcome the eifect of bleaching species decomposition. Operable activators of the instant invention, thus, are those which provide an acceptably high rate of bleach activation. Identification of such activators can be made by a simple test measuring the rate at which the system being tested oxidizes a standard dye material (Polar Blue).

The rate equation for Polar Blue dye oxidation is kinetically expressed as follows:

wherein r is the rate at which the test dye (Polar Blue) is oxidized; k is the rate constant for the oxidation reaction; [K] is the concentration of aldehyde or ketone being tested, [B] is the concentration of peroxygen bleaching agent and [PB] is the concentration of Polar Blue dye being oxidized. If activator and bleach are present in amounts such that their concentrations remain essentially constant relative to that of the Polar Blue being oxidized throughout the reaction, k [K] and [B] can be combined into a single oxidation rate constant, k giving a Polar Blue oxidation rate equation of:

wherein k =k [K] [B].

In a procedure more fully described below, k is determined experimentally by measuring with a spectrophotometer, light absorbence through a Polar Blue dye solution as the Polar Blue dye therein is being oxidized by the bleach-activator system being tested. A plot of the logarithm of light absorbence versus time theoretically yields a straight line, the slope of which is k In order to precisely define the aldehydes and ketones which operate to activate the peroxygen bleaches of the instant invention, a standard Dye Oxidation Rate Determination, is utilized to determine which activators have the requisite bleach activation characteristics. The Dye Oxidation, Rate Determination employing the general principles outlined above, is established as follows:

The oxidation rate constant (kox) determination is made with a water solution containing Oxone (41.5% KHSO 2.7 10- M KHSO in solution), the activator being tested; and Polar Blue dye (6.5 X 10 M Polar Blue in solution). The Polar Blue utilized is Polar Brilliant Blue GAW (marketed by the Geigy Chemical Corporation) recrystallized from acetone/methyl alcohol/benzene. Four grams of Polar Brilliant Blue GAW is stirred at room temperature for about 1 hour in 400 milliliters of acetone plus 400 milliliters of methyl alcohol. This solution is then filtered through Whatman 40 paper. Benzene (1600 milliliters) is added with stirring to the filtrate, and this mixture is stored at 34 F. for 24 hours. The solution is then filtered at 34 F. through Whatman 40 paper and the precipitate dried in room atmosphere. About 20% yield of recrystallized Polar Blue product is obtained.

An appropriate volume of deionized and doubly dis tilled water to yield a final Volume of milliliters and 5 milliliters of an 0.10 wt. percent Polar Blue (as prepared above) solution are placed in a milliliter glass beaker. Oxone is added to the beaker as a solid or from a stock solution to provide an Oxone concentration of 2.7 10 M, and 0.5 N NaOH is added to adjust the solution pH to 9. (This pH is maintained throughout the test by periodic addition of 0.5 N NaOH.) At zero time, the aldehyde or ketone to be tested is added to the mixture as a solid, neat or stock solution to yield a final aldehyde or ketone concentration of 6.8X10 M or lower. (Activator solutions are generally aqueous but activators of low water solubility can be added as ethanol solutions.)

Aliquots are withdrawn for absorbence readings immediately before the addition of activator (Time 0) and at appropriate intervals thereafter (usually 30 second intervals). Absorbence readings of the aliquots are made with any commercial spectrophotometer, measured at the.

)tmaxlmum for Polar Blue (6200 A.). The sampling continues until solution absorbence has been reduced to one half or less of its original value. After the absorbence,

k A (Ln Absorbence) -1 At sec The rate constant, k is approximately directly proportional to the concentration of activator present. Some ketones which are better activators operate efiectively at much lower concentrations than the 6.8X10" M ketone solution concentration Specified above as an upper limit for use in the test. Such activators will, of course, oxidize dye at this higher specified concentration but so quickly that absorbence measurements are diflicult. Accordingly those activators having relatively high k s are tested at concentrations lower than 6.8 10 M with k at this standard concentration being determined by linear extrapolation.

It is, of course, possible to obtain numerical values for k for any given activator according to the above-described Dye Oxidation Rate Determination and limitations on k itself can be used to define operable activators of the instant invention. In order to avoid, however, possible variations in absolute k values due to imprecision in Polar Blue preparation and/ or reagent concentration or quality from test to test, operable activators of the instant invention are defined in terms of a parameter K hereinafter referred to as the Relative Oxidation Constant. K is simply defined as ox-test ox-ac wherein komest is the numerical k obtained for the activator being tested in the above-described Dye Oxidation Rate Determination at an actual or extrapolated activator concentration of 6.8 M, and kmbac is the numerical k obtained in the same Determination for a standard activator, acetone, at the standard concentration of 6.8 1O' M.

For purposes of the instant invention, operable activators for persalt systems of the instant invention include those aldehydes and ketones which produce a Relative Oxidation Constant (K of 0.25 or greater. Preferably persalt activators include aldehydes or ketones which produce a K of 5.0 or greater; highly preferred aldehyde and ketone persalt activators produce a K of 25.0 or greater. Operable activators for peracid systems of the instant invention include those aldehydes and ketones which produce a Relative Oxidation Constant (K of 25.0 or greater. Preferable peracid activators include aldehydes and ketones which produce a K of 200.0 or greater.

The following tables provide representative examples of various types of activators which are operable in the instant invention. Provided for each activator is the k obtained by the Dye Oxidation Rate Determination at an actual or extrapolated activator concentration of and the Relative Oxidation Constant, K

Another operable class of activator compounds is that of aliphatic ketones. Table 2 provides representative examples of aliphatic ketones having the requisite dye oxidation characteristics.

TABLE 2 [Cox-mt X1 (hex-tent I Aliphatic ketone (sec- It...

Trimethylammonioacetone nitrate 53. 0 21. 0 5-diethylb enzylarnmonio-Z-pentanone nitrate 40. 0 16. 0 5-diethylmethylammonio-Z-pentanone nitrate..- 38. 0 15. 0 Methyl pyruvate 47. 0 19. 0 Diethyl keto malonate 22. 0 8. 8 S-hydroxy-Z-butanone- 20. 0 8. 0 Acetol 14. 0 5. 6 Hexachloroacetone 8. 2 3. 3 2,5-hexanedione 6. 3 2. 5 Phenylacetone. 4. 5 1. 8 Ethyl levulinate 2. 8 1. 1 5-hydroxy-2-pentanone 2. 8 1. 1 Acetone 2. 5 1. 0 3 penten-2-one 2.0 0.80 Methyl ethyl ketone l. 8 0. 72 4-hydroxy-3-methyl-2-butanone 1. 1 0. 44 3-pentanone 0.80 0.32 2-heptanone 0. 66 0. 26

Another operable class of activator compounds is that of aromatic ketones. Table 3 provides representative examples of aromatic ketones which have the requisite dye oxidation characteristics.

TAB LE 3 koX-teet K0: 10 (kox-test/ Aromatic ketone (see- 1.

8-hydroxyquinoline. 2, 000. 0 800. 0 4-acetyl-l-methylp 1, 840. 0 740.0 D1-2-pyridyl ketone, N-oxlde 1, 040 0 420.0 2-acetylquinoxaline 120. 48. 0 2-acetyl-3-methylqui 38. 2 15. 4 D1-2-pyridyl ketone... 79. 0 32. 0 G-acetyl-l,2,4-trimethylquinolinium nitrate 57. 0 23. 0 S-hydroxyquinoline, N-oxide 55. 0 22. 0 3-trimethylammonioacetophenone nitrate.. 49. 0 20.0 Methyl phenyl glyoxalate 45. 0 18. 0

N-methyl-p-rnorpholinioacetophenone methylsulfate 16. 0 6. 4 3-acetyl pyridine, N-oxide. 41.0 16.0 p-Nitroacetophenone. 13. 0 5. 2 m-Nitroacetophenone. 38. 0 15. 0 Sodium p-acetyl benzene sulfonate 1. 5 0. 60 pAcetylbenzonitri 5. 0 2. 0 65. 0 26. 0 32. 0 13. 0 4-methoxy-3-nitroacetophenone 11. 0 4. 4 p-Chloroacetophenone. 0. 96 0. 38 p-Diacetylbenzene 6. 1 2. 4 N-methyl-p-morpholinioacetophenone nitrate 42. 0 17. 0 Phenacyltriphenylphosphonium nitrate 7. 2 2. 9 Z-acetyl pyridine 19. 0 7. 6 2-acetyl pyrldine, N-oxide 12. 0 4. 8 3-ac-etyl pyridine- 5. 9 2. 4 4-acetyl pyridine 31.0 12. 0 4acetyl pyridine N-oxide.. 34.0 14.0 2,6-diacetyl pyridine 31.0 12. 0 3-acetyl pyridine, N-oxide 41. 0 16. 0

Another operable class of activator compounds is that of cyclic ketones. Table 4 provides representative examples of cyclic ketones which have the requisite dye oxidation characteristics.

TABLE 4 koxxlm (km-m: Cyclic ketone (seef Ian-M Gyclohexanone 22.0 8. 8 2methyl cyclohexanone 5. 3 2. 1 2,6-dimethyl cyclohexanonen 0. 68 0. 27 3-rnethy cyclohexanone- 16. 0 6. 4 4-ethyl cyclohexanone. 27. 0 11. 0 4-t-butyl cyclohexanone-. 36. 0 14. 0 4,4-dimethyl cyclohexanone 39. 0 16. 0 Methyl 4-oxocyclohexane carboxylate 62.0 25. 0 Sodium 4-oxocyclohexane carboxylate 17.0 6. 8 2-trimethylammoniocyclohexanone nitrate. 11.0 4. 4 4-trlmethyla1nmonicocylohexanone nitrate. 1, 840. 0 740. 0 3oxo-cyclohexyl acetic acid 14. 0 5. 6 Cycloheptanone 1. 2 O. 48 jlA-eyrlnhmmnpdinnn 77, 0 31, 0 Dehydrochloric acid 120. 0 48. 0 Tropinone methonitrate 1,680.0 670. 0 N-me thyl-3-ox0quinuclidinium nitrate 1, 360. 0 544. 0

Another class of operable activator compounds is that of heterocyclic ketones. Representative examples of heterocyclic ketones having the requisite dye oxidation characteristics are shown in Table 5.

l-t-butyl, l-methyM-oxopiperidinium nitrate 1-(4-dodecylbenzyl) l-methyll-oxopiperidinium chloride 2,640 1,060 0 3-(N-methyl-4-oxopiperidinio)-propane sultonate 1, 040. 0 420.0 l-allyl-l-methylA-oxopipelidinium chl0ride 1, 360. 0 540- 0 1-methyll'(l-naphthylmethyl)-4-oxopiperidinium chloride 2, 720 0 1,090 0 1-methyl-1-pentamethylbenzy1-4-ox0piperidinium chloride 2, 560. 0 1, 020. 0 2,2,6,6-tetramethyl-4-piperidone hydrate 240. 0 96.0 1-methyl-4-piperidone, N-oxide 96.0 38.0 N-carbethoxyA-piperidone 230. 0 92. 0 N .N-dirnethyl-N,N-phenylenedimethylene bis(4'0xopiperidinium nitrate 3, 440. 0 1, 380. 0 TetrahydrothiopyranA-one methonitrate 1, 600. 0 640. 0 Tetrahydrothiopyran4one, S,S-dioxide 880. 0 350. 0 Tetrahydrothiopyran-ii-one, S,S,-dioxide 6. 1 2. 4 4-oxaeyclohexanone 220. 0 88. 0

All of the above-described aldehyde and ketone examples are all either commercially available or can obviously be synthesized by the skilled artisan having before him the teaching of the prior art. Gardini et al., J. Chem. Soc. (C), (1970) page 929 and Lyle et al., J. Org. Chem., Vol. 24 (March, 1959), page 342 are examples of such art and are hereby incorporated herein by reference.

Ketones operable in the process and compositions of the instant invention can be in either liquid or solid form. Liquid compositions, however, are generally less physically and chemically stable and are hence not preferred. Preferred dry composition, of course, employ solid aldehydes or ketone-yielding compounds as the activator component. A solid activator is one which is solid at room temperature. Not all of the activators which operate in solution to enhance peroxygen bleaching according to the instant invention are available in solid form at room temperature. Those which are solid, however, include many of the preferred activators.

A number of aldehydes and ketones which are operable in the instant bleaching process are liquids at room temperature but can for use in dry compositions be put in solid form by reacting them with sodium bisulfite. Synthesis of these bisulfite addition products is a common reaction of aldehydes and some ketones and is described, for example, on page 298 of Cram and Hammond, Organic Chemistry, Second Edition, (McGraW-Hill, 1964). aldehydes and ketones which are not branched near the functional group add bisulfite ions in aqueous solution. The products are a-hydroxysulfonates which can be crystallized as sodium salts.

In aqueous solution at the pHs of the instant process these bisulfite compounds, i.e., a-hydroxysulfonates, will dissolve to yield the ketone or aldehyde and bisulfite. However, because bisulfite is capable of rapidly reducing the peroxygen bleaching agent, the mole ratio of the bisulfite addition product to peroxygen bleach is preferably maintained at less than 1:1 in concentrated compositions.

Examples of aldehydes and ketones which form such solid bisulfite addition products include acetaldehyde, butraldehyde, benzaldehyde, acetone, methyl ethyl ketone, methyl pyruvate, cyclohexanone and some substituted cyclohexanones.

For use in the bleaching activation process of the instant invention activator is generally present in aqueous solution to the extent of from about 0.1 p.p.m. to about 10,000 p.p.m. Preferred activator solution concentrations depend upon the desired end result for which the instant activation process is used.

As can be seen from the description above of the bisulfite addition compounds and from the recitation of certain hydroxyquinoline compounds, not all activators for use in concentrated bleaching compositions are necessarily aldehydes or ketones in concentrated or nonaqueous form. All activators of the present invention do, however, yield an aldehyde or ketone species in aqueous solution. An essential element of the instant invention is the presence of an aldehyde or ketone species in solution to activate the particular peroxygen compounds employed. Accordingly the term activator when utilized to describe components of the concentrated compositions of the instant invention is used to include compounds which yield an aldehyde or ketone in aqueous solutions.

Activator is present in the instant bleaching composition to the extent of from about 0.01% to about 75% by Weight. Preferred activator concentrations depend upon the particular use to which the activated bleaching compositions of the instant invention are put, and are dis cussed more fully hereinafter.

The Buffering Agent The bleach activator process of the instant invention is carried out in aqueous solution having a pH of from about 7 to about 12. Outside this pH range, bleaching performance falls off markedly. Since an aqueous solution of the persalts or peracids of the present invention is generally acidic, it is necessary to maintain the requisite pH conditions by utilization of standard buffering agents. A buffering agent is, of course, any non-interfering compound which can alter and/or maintain pH, such as any standard buffering agent or combination. For example, phosphates, carbonates, or bicarbonates which butter within the 7-12 pH range are useful. Examples of suitable butfering agents include sodium bicarbonate, sodium carbonate, disodium hydrogen phosphate and sodium dihydrogen phosphate. Other buffering compositions for any desired pH can be obtained by the skilled artisan from any standard chemistry handbook or textbook. Buffering agents generally comprise from about 1% to about by weight of the instant concentrated bleaching compositions.

Direct Fabric Bleaching The instant bleach activation process and compositions can be employed to carry out direct bleaching of stains on fabrics. Fabric bleaching is realized by contacting stained fabrics with an aqueous bleaching solution containing peroxygen compound dissolved in amounts sufficient to provide from about 10 p.p.m. to about p.p.m. available oxygen and activator compound dissolved in amounts suflicient to provide from about 250 p.p.m. to about 10,000 p.p.m. activator. Bleaching solution pH is generally maintained between 7 and 12. For persalt systems pH preferably varies between 8 and 10; for peracid systems pH preferably systems pH preferably varies between 7 and 10.

Concentrated compositions especially suited for direct fabric bleaching generally contain from about 5% to about 75% by weight of the peroxygen compound and from about 5% to about 75 by weight of an aldehydeor ketone-producing activator. Concentrated fabric bleaching compositions also preferably contain from about 5% to about 60% by weight of a buffering agent suflicient to maintain a bleaching solution pH of from about 7 to 10.

Preferred peroxygen bleaching agents for fabric stain removal include potassium monopersulfate, diperazelaic acid, and diperisophthalic acid. Preferred activators for fabric stain removal systems include methyl 4-oxo-cyclohexane carboxylate, acetol, 3-oxo-cyclohexyl acetic acid, cyclohexanone, sodium 4-oxo-cyclohexane carboxylate, acetone, 4-ethylcyclohexanone, cycloheptanone, S-diethylmethylammonio-Z-pentanone nitrate, N-methyl-p-morpholinioacetophenone nitrate, methyl ethyl ketone, 3- pentanone and 1,4-cyclohexanedione.

A highly preferred embodiment of the instant fabric bleaching compositions comprises the optional addition of a water-soluble chloride salt. In bleaching solutions such salts provide a source of chloride ions which then are oxidized in the presence of the activated peroxygen species to yield bleaching of a hypochlorite nature.

Although some of the chloride ions are oxidized to hypochlorite during the instant fabric bleaching process, it is still meaningful to specify a solution concentration of the chloride component in terms of parts per million (p.p.m.) of theoretical or initial chloride ion. Accordingly, water-soluble chloride salts are preferably added to aqueous fabric bleaching solutions in an amount effective to provide therein from about 50 p.p.m. to 1000 p.p.m. When utilized, chloride salt is added to compositions containing the peroxygen bleach, activator and buffer compounds in an amount of from about 1% to 50% by weight of such compositions. A preferred chloride salt range for such four component fabric bleaching compositions from about 4% to 40% by weight. Suitable Water-soluble salts include the chloride salts of sodium, potassium, calcium and magnesium. Sodium chloride is preferred.

When chloride salts are utilized in the above-described preferred fabric bleaching compositions, the activator compound acts to promote generation of hypochlorite bleaching species as well as to activate peroxygen bleaching. Certain activator compounds are preferred for use in direct fabric bleaching processes and compositions because of their exceptional ability to promote hypochlorite generation. These activators include those producing a Relative Oxidation Constant of 1.0 or greater such as acetone; tetrahydrothiopyran-4-one,S,S-dioxide; cyclohexanone sodium bisulfite adduct; di-Z-pyridyl ketone; methyl pyruvate; chloral hydrate; cyclohexanone, S-diethylbenzylammonio-Z-pentanone nitrate; 1-methyl-4-piperidone oxide and the ketones which form cations or zwitterions in solution. Examples of such ion-forming ketones include 3-(N methyl-4-oxopiperidinio)-propane sulfonate; tropinone methonitrate; tetrahydrothiopyron-4-one methonitrate; 1-benzyl-4-piperidone methonitrate; and 1,1- dimethyl-4-oxopiperidinium nitrate.

Some activators, on the other hand, apparently react with chloride to form chlorinated compounds faster than they promote generation of hypochlorite species. Such ketones are not preferred for use with the above-described chloride embodiment. The only known activators of this kind are acetophenone type compounds without substituents on the a-methyl carbon atom. (For example, 3-trimethylammonioacetophenone nitrate, 2-acetylquinoxaline and 3-acetyl pyridine, N-oxide.)

In general, activator concentrations for the chloride embodiment of the present invention can be lower than those employed when chloride is not utilized. A fabric bleaching process employing chloride ion preferably uses from about to 200 p.p.m. activator in bleaching solution. Concentrated fabric bleaching compositions utilizing the preferred chloride salt embodiment generally contain from about 0.2% to about 40% by weight of activator compound.

The direct fabric bleaching compositions of the instant invention can, of course, be incorporated as one component into other laundry care formulations. Such formulations can contain in addition to the instant bleaching system such ingredients as non-interfering synthetic detergents, builders, perfumes, coloring agents, solubilizing agents, fillers, etc. These additional components, however, must not interfere with the essential chemical or physical functioning of the instant activated bleaching compositions.

Hard Surface Bleaching The instant bleach activation process and compositions can also be employed to carry out stain removal on hard surfaces. Hard surface bleaching is realized by contacting stained hard surfaces with an aqueous bleaching solution containing peroxygen compound dissolved in amounts sufficient to provide from about 200 p.p.m. to about 2000 p.p.m. available oxygen and activator compound dissolved 12' in an amount sufiicient to provide from about 100 p.p.m. to about 2000 p.p.m. activator. Bleaching solution pH is again generally maintained between 7 and 12. For persalt systems pH preferably varies between 8 and 12; for peracid systems, pH preferably varies between 7 and 11.

Concentrated compositions especially suited for hard surface bleaching preferably contain from about 1% to about 25% by weight of the peroxygen compound and from about 0.01% to about 5% by weight of an aldehydeor ketone-producing activator. Concentrated hard surface bleaching compositions also preferably contain from about 1% to about by weight of the abovedescribed buffering agent sufiicient to maintain a bleaching solution pH of from about 7 to 12.

Preferred peroxygen bleaching agents for hard surface stain removal include potassium monopersulfate, diperazelaic acid and diperoxyisophthalic acid. Preferred activators for hard surface stain removal systems are those having a Relative Oxidation Constant (K of 25 or greater and include di-Z-pyridyl ketone; 1,1-dimethyl-4-oxopiperidinium nitrate; 1-benzyl-4-piperidone methonitrate; 8-hydroxyquinoline; tetrahydrothiopyran-4-one,S,S-dioxide; 1-benzyl-4-piperidone methochloride; 3-(N-methyl-4-oxopiperidinio)propane sulfonate; 2,2,6,6-tetramethyl-4-piperidone hydrate; N-carbethoxy-4-piperidone and tetrahydrothiopyran-4-one methonitrate.

A highly preferred embodiment of the instant hard surface bleaching composition comprising the optional addition of a water-soluble chloride or bromide salt. In bleaching solutions such halide salts provide a source of chloride or bromide ions which then are oxidized in the presence of the activated peroxygen species to yield bleaching of a hypochlorite or hypobromite nature.

Although some of the halide ions are oxidized to hypohalite during the instant hard surface bleaching process, it is still meaningful to specify a solution concentration of the halide (chloride or bromide) component in terms of parts per million (p.p.m.) of theoretical or initial halide ion. Accordingly, water-soluble chloride or bromide salts are preferably present in aqueous hard surface bleaching solution in an amount of from about 1000 p.p.m. to 50,000 of theoretical halide ion.

When utilized, chloride or bromide salt is added to compositions containing the peroxygen bleach activator with buffer compounds in an amount of from about 0.5% to 70% by weight of such compositions. A preferred halide salt range for such four component hard surface bleaching compositions is from about 1.0% to 50% by weight. Suitable water-soluble salts include the chloride and bromide salts of sodium, potassium, calcium and magnesium. Sodium chloride and sodium bromide are preferred.

Dye Transfer Inhibition Another potential use for the peroxygen bleach-activator-buffer combination of the instant process and compositions involves elimination or reduction of the transfer from one fabric to another of dye released into laundering solution from colored fabrics during conventional laundering of such colored fabrics. The instant three component combination can be utilized either alone or in conjunction with other conventional laundering materials to bring about such a reduction of dye transfer. When employed for the purpose of inhibiting dye transfer in laundering solution, the instant peroxygen bleach activation process can be carried out by utilizing in such aqueous laundering solution sufficient peroxygen bleach to provide from about 2.5 p.p.m. to tabout 50 p.p.m. available oxygen and suflicient activator to provide from about 0.1 p.p.m. to about 500 p.p.m. aldehyde or ketone.

Solution pH is, of course, maintained by a buffering agent between 7 and 12. For presalt systems, pH preferably varies between 8 and 10; for peracid systems, pH preferably varies between 7 and 10.

Concentrated compositions containing only the peroxyconventional fabric laundering compositions, the peroxygen bleach-activator-buffer component in such formulations has the preferred bleach, activator, and buffer concentrations specified above, and the combination is incorporated into the total composition to the extent necesgen compound, act1vator and buffer preferably contaln sary to provide the requ1s1te bleach and activator concenfrom about 1% to about 50% by Welght p r xygen COHI- tration in laundering solution when the conventional laun- Pf from about 0.04% to about 6 5% by welght twdering formulation is dissolved. A highly preferred dye tlvator P from 1% 75% y Welght transfer inhibition execution utilizing the instant peroxyof a buffer Sllfficlent t0 a l Solution P between gen bleach-activator-buffer system is realized by combin- 7 and 12 $1611 composltlons are to be used for the ing such a system with zwitterionic surfactants. This purpose of inhlbltmg ye transferhighly effective dye transfer inhibition system is the sub- Preferfed Q y COIPPOUHdS {ltlhzatlon dye ject of the copending US. patent application of J. Paul transfer inh1b1t1on systems include potassmm monopersul- J n h i 230 51 fil d 29 1972 fat? and dlperoxylsophthallc acld- Preferred afltlvators are 15 other highly preferred dye transfer inhibition execution of those havlng a ox greajlef Include Such the instant composition invention involves utilization of cofnpolmdsfis 'PY Y 'PY Y *1- the peroxygen bleach-activator-buifer combination with oxide; m-mtroacetophenone, p-nitroacetophenone; p-d1- certain l i l compounds h as l i l liacetyl'benzene; cyclohexanone; methyl pyruvate; 8-hydroxdone. Dye transfer inhibiting systems of this type are deyquinoline; 8-hydroxyquinoline, N-oxide; 2-acetylqu1noxoscribed in the copending US. patent application of J. Paul line; 2-acetyl-3-methylquinoxaline; Z-acetylpyridine; 3- Jones, having Ser. No. 230,491, filed Feb. 29, 1972. acetylpyridine- N- oxide; 4-acetylpyridine-N-oxide; 3-tri- The bleach activation process and bleaching composimethylacetophenone nitrate; 4 trimethylammonioacetotions of the instant invention are illustrated by the followphenone nitrate; tetrahydrothiopyran 4 one-S,S-dioxide; ing examples. N-methyl-p-morpholinioacetophenone nitrate; 1-methyl-4 Several bleaching compositions of the instant invention piperidone methonitrate; l-benzyl-4-piperidone methoniare set forth in Table I.

TABLE I Example number Component I II III 1V V VI vII VIII IX X XI XII XIII XIV XV XVI XVII XVIII XIX Oxone 28 9.3 9.3 9.3 9.3 45 19.2 16.6 31.4 33.2 33.2 30.3 29.6 Dipei acid" 9.1 20.1 Diperisophthalie acid 8. 0 17. 9 Acetone (Kox=1-0) 46. 5 Methyl ethyl ketone (K.,,=0.72) 46.5 Cyclohexanone (K..==8.8)... 28 5 3-pentanone "=0. 46.5 1,4-cyclohexanedione 0: .0 46.5 1,1-dimethyl-4-oxopiperidinium nitrate (K...=930.0)- 1.2 1-benzyl-4-piperidone methochloride (K..,=s0o.0) 0.4 0.4 1.06 13.8 13.4 Di-2-pyridyl ketone ox 61.5 60.8 p-Nitmagetophenone 9 7 Tetra liydrothiopyran- 4-one,S,S-dioxide (K.,,=360.0) 6.3 4-trimethylamrnoniocyclohexanone nitrate (K.,,.=770.0) 1.32 2-acetyl-3-methylquinoxaline (Ka1=15.4 11.8 Cyclohexanone sodium bisulfite adduct (K..=.=3.9) 9 Sodium carbonate 19.2 19.3 19.3 10.3 22.5 22.0 25.0 30.4 Sodium bicarbonate. 24.8 24.9 24.9 24.7 22.5 23.0 Disodium hydrogen phosphate- 44. 2 tng iyphosphata 62.3 65. 74 65.5 60.0 58.6 30.5 68.3 30.1 66.5

1 A commercially-available bleaching agent containing approx. 41.5% by weight KHSOs, the balance being KHSO4 and K2804 in about equal proportions.

trate; l-benzyl-4-piperidone methochloride; S-diethylmeth- 60V ylammonio-2-pentanonenitrate and S-benzyldiethylammonio-2-pentanone nitrate. Preferred buffering agents for dye transfer inhibition systems include the standard phosphate and carbonate salts commonly found in commercial detergent formulations.

As noted, peroxygen compound, activator and buffer can be used alone as a dye transfer inhibiting concentrated composition which can then be added to conventional laundering solutions. The peroxygen bleach-activator-buffer combination can also be utilized as one component of laundering compositions containing, in addition to the dye transfer inhibition system, conventional fabric laundering agents. Such optional material, of course, incluudes surfactants, builders, enzymes, corrosion inhibitors, perfumes, and coloring agents. When incorporated into such Examples I-V of Table I represent compositions of the instant invention which can be employed as direct fabric bleaching compositions. Examples VI-VIII represent compositions which are especially suitable for direct fabric bleaching when utilized in combination with a source of chloride ion. Examples IX and X represent compositions of the instant invention especially suitable for incorporation into hard surface cleaning compositions. Examples XI-XIX represent compositions especially suitable for inhibiting dye transfer in commonly encountered fabric laundering solutions. Utilization of these compositions in carrying out the bleach activation process of the instant invention is illustrated as follows:

Direct Fabric Bleaching The following tests serve to illustrate the direct fabric bleaching performance of the process and compositions 15 of the instant invention. Stained fabric test swatches are Washed in a Tergotometer (United States Testing Company) operated at a constant agitation rate of 80 c.p.m. for all experiments. Unless otherwise stated, runs are made is run through the solution and padded. The strained cloth is then dried in an oven. Two applications are given.

Bleaching Performance Test Table H describes various bleaching solutions which at 120 for mmutes Swatches graded before were used to demonstrate the effectiveness of the instant and after bleaching on a Hunter Color Difference Meter. bleaching process in removing stains f the above- An initial and final whiteness grade is calculated from the described cloth swatch s,

TABLE II Solution number Solution concentration 1 2 3 4 5 6 7 8 9 10 11 12 Component, p.p.m.:

Potassium monopersultate Average 01.... 44 44 44 44 44 44 44 44 44 44 44 44 Cyclohexanone (K ox=8.i ..1, 000 100 Cyclohexanone sodium bisulfitc adduct (K=8.8)- {666 200 Acetone (K nx=1-O) Methyl ethyl ketone (K 0 7 3-pentanone (K x=0.32) 1,4-eyclohexanedione (K o: 1.0 T

l,1-dirnethyl-4-oxopiperldinlum nitrate (K u=930.0) Sodium chloride Temperature F.) 0

pH 9.0 9.0 9.0 9.0 8.0 9.0 9.0 9.0 9.0 90 9.0 9.0 AW W 11.4 11.3 9.9 7.2 10.8 13.1 12.8 18.3 3.6 6.4 6.3 18.3

Hunter color coordinates (L,a,b) for each swatch through Solutions 1-5 simulate bleaching solutions obtained the use of the whiteness equation.

W=100 /(100--L) +a +b and the color differences AW, so obtained are taken as a measure of stain removal performance. The average AW values for five stains are reported (grass, tea, wine, gravy and Empa-Sulfur Black). A AW difference of 2 units is readily apparent to the human eye.

In the stained swatch experiments the pH of the bleaching solution was usually maintained by the use of a Radiometer pH-stat (Model TTIl). Sodium hydroxide (usually 1.0 N) was used as the titrant.

Preparation of Stained Swatches The swatches used in the development of these tests are obtained from several sources. The respective swatches and their sources (commercial or method of preparation) are outlined in the following summary.

Empa-Sulfur Black and Red Wine These cloth samples are obtained commercially from Test Fabrics, Inc., 55 Vandam St., New York 13, N.Y., manufactured by E.M.P.A., Unterstasse II, 9001 St. Gall, Suisse.

Grass Stain 200 g. of freshly cut untreated grass is mixed with 1000 cc. of 5 gr./gal. hardness water in a Waring Blender until a uniform slurry is produced. This slurry is strained through cotton, and the resulting extract is used in an Atlas Electric Padder by passing the cloth through three successive times. The cloth is aged three days and stored in the dark.

Tea

6 ounces of Lipton tea is added to 1 /2 gallons of 5 gr./ gal. hardness Water and simmer-boiled for 2 hours. The solution is filtered through cotton cloth and liquor made up to 1 /2 gallons with hot water. Two square yards of cotton are immersed into the 3% tea solution. The temperature is raised to boil and maintained for two hours. The cloth is lifted out of the liquor and transferred to about 3 gallons of 5 gr./ gal. water (pH=9.5) at 100 F. to rinse. Wringing is done using the Atlas Electric Padder. The cloth is ironed to fix the stain and allowed to age for three days at 120 F.

Gravy A one-ounce package of Durkees brown gravy mix is mixed with 1 cup of water and brought to a boil with stirring. The mixture is removed from the heat and stirred with a high-shear homogenizer for 5 minutes. The warm gravy solution is then placed in a container and the cloth Percent wt. Composition of Example V I (Table I) 93.5 NaCl 6.5

is dissolved in water to the extent of 0.228% by weight. Solution 7 simulates a bleaching solution obtained when a composition consisting of:

Percent wt. Composition of Example VII (Table I) 89 NaCl 11 is dissolved in water to the extent of 0.250% by weight. Solution 8 simulates a bleaching solution obtained when a composition consisting of Percent wt. Composition of Example VIII (Table I) 88 NaCl 12 is dissolved in water to the extent of 0.228% by weight.

Solutions 9 and 10 represent prior art nonactivated peroxygen bleaching solutions. Solution 11 represents a typical prior art halide-peroxygen bleaching solution. Solution 12 represents a typical prior art hypochlorite bleaching solution. As can be seen from the AW values corresponding to the various solutions, the instant bleaching process provides superior stain removal performance under a variety of bleaching conditions. The particular efficacy of the preferred halide embodiment is also demonstrated.

Substantially similar stain removal results are obtained when the potassium monopersulfate in Solution 8 is replaced with dipotassium monoperphosphate, diperoxyisophthalic acid, diperadipic acid, diperazalaic acid, soduim diperoxyisophthalate or potassium diperazelate in similar concentrations.

Substantially similar stain removal results are obtained when the activators of Solutions 1-5 are replaced with methyl 4-oxo-cyclohexanecarboxylate; 3-oxo cyclohexyl acetic acid; chloral hydrate; acetaldehyde; butraldehyde; benzaldehyde; sodium 4-oxo-cyclohexane carboxylate; 4- ethylcyclohexanone; cycloheptanone; S-diethylmethylammonio-2-pentanone nitrate; 4-trimethylammoniobenzaldehyde methyl sulfate; acetol or N-methyl-p-morpholinioacetophenone nitrate in similar concentrations.

Substantially similar stain removal results are obtained when the activators of Solutions 6, 7 and 8 are replaced with acetone; di-2-pyridyl ketone; methylpyruvate; chloral hydrate; tetrahydrothiopyran-4-one,S,S,-dioxide; l-meth- 17 yl-4-piperidone oxide; 3-(N-methyl 4 oxopiperidinio-) propane sulfonate; 5-diethylbenzylammonio-2-pentanone nitrate; tropinone methonitrate; tetrahydrothiopyran-4- one methonitrate; or l-benzyl-4-piperidone methonitrate.

Substantially similar stain removal results are obtained when the cyclohexanone sodium bisulfite of Solution 7 is replaced with the bisulfite addition products of acetaldehyde, butraldehyde, benzaldehyde, acetone, methyl pyruvate or methyl ethyl ketone in similar concentrations.

Hard Surface Cleaning Bleaching compositions of the instant invention were incorporated into typical hard surface cleanser formulations and such formulations tested for stain removal. Table III describes three hard surface cleaning formulations. Compositions a and b utilize compositions of Examples IX and X of Table I in conjunction with other conventional cleanser components. Composition c represents a commercially available sodium hypochloride-containing bleach, Comet.

These three compositions are tested for their ability to quickly remove stains from a standard hard surface material. Etched porcelain plates were stained with a so lution of ferrous tannate and with a commercially available grape juice. The tannate stain was set by sprinkling sodium carbonate crystals onto the wet stain and the grape juice stain was set by sprinkling ferrous sulfate crystals onto the wet stain. 25% solutions of the composition samples in 10 grain/gallon city water were prepared and poured slowly and continuously over the stain spots until the stains were removed. The time needed to remove each spot was recorded. The Average Time to Bleach is an average of four runs on four different sets of spots. The lower the elapsed time, the faster is the bleaching. Results appear in Table III.

TABLE 111 Composition Component, wt. percent a b e 833333333 ir dfitfi iiki32:11:13::jinf'f'i- Sodium chlor Sodium dodecyl benz e sulfonat Hydrated lime 1 Water and minors Balance Balance Com er 100 25% solution pH 11. 8. 15 Average time to bleach-tannin, seconds 6 13 7-10 Average time to bleach-grape uice,

seconds 2 8 4 Dye Transfer Inhibition Solutions simulating several dissolved compositions of Table I were tested for their ability to inhibit dye transfer. Dyed fabrics and white tracer fabrics were washed together in aqueous solution containing the components of various Table I compositions in concentrations corresponding to those obtained when such compositions are dissolved for standard laundering operations. A Gardner Color Difference Meter was used to measure pickup by the tracer fabrics of dye released into solutions by the dyed fabrics. The dyed fabrics employed are shown in Table IV.

TABLE IV Weight Dye type Color Fabric grams Acid Blue Wool, double knit 3.8 Amie Rerl Cotton 1, 6 Oran e dfl 1,6 Green Sweatshirt 1. 0 Yellow do 3.2 -Rlno do 3, 2 Maroon do 4.2 Pink Polyester, double knit 0. 5 (in rln 0,5 Blue 91% Arnel triacetate 9% 2.0

knit. Rod (in 2,0 Purple Cotton 0.4 Yellow do 0.4 Blue do 0. 4 Purple Terry cloth. 3.4 Do Blue Denim 3.4

TotaL 31.6

The white tracer fabrics employed were 3 /2 x 3 /2 inch swatches obtained from Testfabrics, Inc., and are characterized as shown in Table V.

TABLE V Multifiber Strip Cotton Terrycloth Cotton x 80 print cloth Polyester/cotton 65/ 35 blend Orlon Dacron, spun Nylon, double knit Nylon, spun Acetate taffeta Silk crepe Polyester continuous filament Total weight 14 gms.

Dyed and tracer fabrics were placed in a 1 liter Tergotometer, and various loads were washed for 10 minutes at 105 F. for each solution tested. For all testing water at 7 grains/gallon hardness was employed with pH being maintained at about 9. After each run the whiteness of the cotton terrycloth tracer swatches was ascertained using a Gardner Color Difference Meter. Whiteness (W) was calculated according to the following formula:

wherein L, a and b are the Gardner Meter lightness and chromaticity coordinates. Meter readings were made using a single layer thickness of fabric and white standardization and backup plates.

Eifectiveness of a particular dye transfer inhibition system was measured by establishing a parameter called the Percent of Dye Transfer Reduction (percent DTR) utilizing the above-defined whiteness values. Percent DTR measures the improvement in dye transfer inhibition realized by the system being tested over that occurring when the dyed and tracer fabrics are washed together in a solution containing a commercial granular built detergent, Tide, from which fluorescers had been removed. Thus P t DTR ercen WFFD wherein percent DTR is Percent Dye Transfer Reduction; W is the Gardner Meter Whiteness of tracer cloths washed with the dyed fabrics in fluorescer-free Tide; W is the Gardner Meter Whiteness of tracer cloths washed with the dyed fabrics in the composition being tested; and W is the Gardner Meter Whiteness of tracer cloths washed by themselves in fluorescer-free Tide.

Dye transfer performance of various solutions simulating aqueous solutions of Table I compositions is demonstrated by Table VI. The first column characterizes major components of the laundering solution being tested. The solutions A-I simulate solutions obtained by dissolving respectively compositions of Examples XI-XIX (Table 19 I) along with 505 p.p.m. of fluorescer-free Tide from which the sodium tripolyphosphate builder had been removed. (The sodium tripolyphosphate butler from the Examples XI-XlX compositions in combination with the builderless Tide simulates a 1000 p.p.m. solution concentration of fully-built Tide.) The second column provides the sum of the Percent Dye Transfer Reduction (percent DTR) as defined above obtained for the cotton terrycloth tracer material and for the double knit Nylon tracer cloth.

TABLE VI Percent Solution (major components) DTR sum A 1,000 p.p.m. Tide (fiuorescer free); 250 p.p.m. oxone (11 p.p.m. average 02); 60 p.p.m. tetrahydrothiopyran-t-ono, S,S-dioxide (Ku=350.0)

B 1,000 p.p.m. Tide (fluorescer-tree); 250 p.p.m. oxone (11 p.p.m. average Oz); 8 p.p.m. 1-benzy1-4-piperidone methoehloride (Ku=800.0)

1,000 p.p.m. Tide (fiuorescer-iree); 250 p.p.m. oxone (11 p.p.m. average 02); 10 p.p.m. 4-trimethylammoniocyclohexanone nitrate (Ko,=770.0)

D 1,000 p.p.m. Tide (fiuorescer-lree); 250 p.p.m. oxone (11 p.p.2m. average 02);80 p.p.m. p-nitroacetophenone (K01 =6.

E 1,000 p.p.m. Tide (fluorescer-free); 250 p.p.m. oxone (11 p.p.m. average 02); 100 p.p.m. 2-acetyl-3-methylquinoxaline (Kox=15-4) F 1,000 p.p.m. Tide (fiuoreseer-free); 130 p.p.m. dipensophthalic acid (21 p.p.m. average Oz); 1,000 p.p.m. D1-2- pyridyl ketone (Ko,=32.0)

G 1,000 p.p.m. Tide (fiuorescer-iree); 130 p.p.m. dipensophthalic acid (21 p.p.m. average 02); 100 p.p.m. l-benzyl- -piperidonemethochloride (Ku= 00.0)

H 1,000 p.p.m. Tide (fluoreseer-tree); 150 p.p.m. diperazelaic acid (22 p.p.m. average 02); 1,000 p.p.m. Di-2-pyr1dyl ketone (Kox=32.0)

I 1,000 p.p.m. Tide (fluorescer-tree); 150 p.p.m. diperazelaic acid 2 p.p.m. average Oz); 100 p.p.m. 1-benzyl-4-piperiodne methochlorlde Kox=800.0)

The Table VI data demonstrate the dye transfer inhibition efficacy of compositions of the instant invention in a standard anionic detergent formulation, for both cotton and Nylon fabric types, with a variety of peroxygen bleach and ketone activator compounds.

Substantially similar dye transfer inhibition is obtained when the activators of Solutions A-I are replaced with di 2 pyridyl ketone, N-oxide; p-diacetylbenzene; mnitroacetophenone; cyclohexanone; methyl pyruvate; 8- hydroxyquinoline; 8-hydroxyquinoline, N-oxide; 2-acetylquinoxaline; Z-acetylpyridine; 3-acetylpyridine N oxide; 4 acetylpyridine N oxide; 3 trimethylacetophenone nitrate; N methyl p morpholinioacetophenone nitrate; 1 methyl 4 piperidone methonitrate; 1 benzyl 4- piperidone methonitrate; 5 diethylmethylammonio 2- pentanone nitrate; or 5 benzyldiethylammonio-2-pentanone nitrate.

Other examples of preferred dye transfer inhibition systems employing the compositions of the instant invention in conjunction with zwitterionic surfactants are found in Examples H-XIII of the copending U.S. Patent application of J. Paul Jones, entitled, Laundering Adjunct and having Ser. No. 230,518, filed Feb. 29, 1972, now abandoned and herein incorporated by reference.

Other examples of preferred dye transfer inhibition systems employing the compositions of the instant invention in conjunction with polyvinyl compounds are found in Examples l1-XI of the copending U.S. Patent application of J. Paul Jones, entitled Laundering Aid, and having Ser. No. 230,491, filed Feb. 29, 1972, now abandoned and herein incorporated by reference.

What is claimed is:

1. A process for activating peroxygen bleaching agents consisting essentially of conjointly dissolving in aqueous solution effective amounts of:

(a) a peroxygen bleaching agent selected from the group consisting of water-soluble monopersulfates and water-soluble monoperphosphates;

(b) an activator selected from the group consisting of aldehydes and ketones, said activator producing a Relative Oxidation Constant of 0.25 or greater; and

(c) a buffering agent to maintain the pH of said aqueous solution within the range of from about 7 to 12.

2. A process in accordance with Claim 1 (a) wherein the bleaching agent is selected from the group consisting of sodium monopersulfate and potassium monopersulfate and is present in an amount sufficient to provide from about 2 p.p.m. to 2000 p.p.m. available oxygen in aqueous solution; and

(b) wherein the activator produces a Relative Oxidation Constant of 5.0 or greater; and is present in an amount sufiicient to provide from about 0.1 p.p.m. to about 10,000 p.p.m. of activator in aqueous solution.

3. A concentrated peroxygen bleach-containing composition consisting essentially of:

(a) from about 1% to about by weight of a peroxygen bleaching agent selected from the group consisting of water-soluble monopersulfates and water-soluble monoperphosphates;

(b) from about 0.01% to about 75% by weight of an activator selected from the group consisting of aldehydes, ketones, 1:1 aldehyde bisulfite adducts, 1:1 ketone bisulfite adducts, and hydroxyquinoline compounds, said activator producing a Relative Oxidation Constant of 0.25 or greater; and

(c) from about 1% to about by weight of a buffering agent capable of maintaining the pH of an aqueous solution containing said peroxygen bleaching agent and said activator within the range of from about 7 to 12.

4. A composition in accordance with Claim 3 especially adapted for bleaching stains on fabrics wherein:

(a) the peroxygen bleaching agent is potassium monopersulfate and is present to the extent of from about 5% to about 75 by weight;

(b) the activator is present to the extent of from about 5% to 75% by weight; and

(c) the buffering agent is capable of maintaining aqueous bleaching solution pH within the range of from about 7 to 10.

5. A fabric-bleaching composition in accordance with Claim 4 wherein the activator is selected from the group consisting of methyl 4 oxo cyclohexane carboxylate; acetol; 3 oxo cyclohexylacetic acid; cyclohexanone; sodium 4-oxo-cyclohexane carboxylate; acetone; 4-ethylcyclohexanone; cycloheptanone; S-diethylmethylammonio- 2 pentanone nitrate; N methyl p morpholinio-acetophenone nitrate; methyl ethyl ketone; 3-pentanone and 1,4-cyclohexauedione.

6. A concentrated composition especially adapted for bleaching stains on fabrics, said composition consisting essentially of:

(a) from about 5% to about 75 by weight of potassium monopersulfate;

(b) from about 0.2% to about 40% by weight of an activator selected from the group consisting of aldehydes, ketones, 1:1 aldehyde bisulfite adducts, 1:1 ketone bisulfite adducts, and hydroxyquinoline compounds, said activator producing a Relative Oxidation Constant of 1.0 or greater;

(0) from about 1% to about 85 by weight of a buffering agent capable of maintaining the pH of an aqueous solution containing said peroxygen bleaching agent and said activator within the range of from about 7 to 10; and

(d) from about 1% to about 50% by weight of a Watersoluble chloride selected from the group consisting of sodium chloride, potassium chloride, calcium chloride and magnesium chloride.

7. A fabric-bleaching composition in accordance with Claim 6 wherein:

(a) the activator is selected from the group consisting of actone; tetrahydrothiopyran 4 0ne,S,S-di0Xide; 1:1 cyclohexanone sodium bisulfite adduct; di-2- pyridyl ketone; methyl pyruvate; chloral hydrate; cyclohexanone; 5 diethylbenzylammonio 2 pentanone nitrate; 1 methyl 4 piperidone, N-oxide;

3 (N methyl 4 oxopiperidinio)propane sulfonate; tropinone methonitrate; tetrahydrothiopyran- 4-one methonitrate; 1 benzyl 4 piperidone methonitrate; and 1,1 dimethyl 4 oxopiperidinium nitrate; and

(b) the water-soluble chloride is selected from the group consisting of sodium chloride, potassium chloride, calcium chloride and magnesium chloride, and is present to the extent of from about 4% to about 40% by weight.

8. A method for bleaching fabrics consisting essentially of contacting said fabrics with an aqueous solution consisting essentially of:

(a) a potassium monopersulfate peroxygen bleaching agent present in an amount suflicient to provide from about 10 p.p.m. to about 100 p.p.m. available oxygen in solution;

(b) an activator selected from the group consisting of acetone; tetrahydrothiopyran 4 one,S,S dioxide; 1:1 cyclohexanone sodium bisulfite adduct; di 2- pyridyl ketone, methyl pyruvate; chloral hydrate; cyclohexanone; 1 methyl 4 piperidone oxide, 3(N- methyl 4 oxopiperidinio) propane sulfonate; tropinone methonitrate; tetrahydrothiopyranl-one methonitrate; 1 benzyl 4 piperidone methonitrate; and 1,1-dimethyl 4 oxopiperidinium nitrate, present in an amount sulficient to provide from about 10 p.p.m. to about 200 p.p.m. activator in solution;

(c) a water-soluble chloride selected from the group consisting of sodium chloride, potassium chloride, calcium chloride and magnesium chloride present in an amount suflicient to provide from about 50 p.p.m. to 1000 p.p.m. theoretical chloride ion in solution; and

(d) a buffering agent capable of maintaining the pH of said aqueous solution within the range of from about 8 to 10.

9. A composition in accordance with Claim 3 especially adapted for bleaching stains on hard surfaces wherein:

(a) the peroxygen bleaching agent is potassium monopersulfate and is present to the extent of from about 1% to about 25% by weight; and

(b) the activator is present to the extent of from about 0.01% to about by weight.

10. A hard-surface bleaching composition in accordance with Claim 9 wherein the activator produces a Relative Oxidation Constant of 25 or greater.

11. A hard-surface bleaching composition in accordance with Claim 10 wherein the activator is selected from the group consisting of 1,1 dimethyl 4 oxopiperidinium nitrate; 1 benzyl 4 piperidone methonitrate; di-2- pyridyl ketone; 1 benzyl 4 piperidone methochloride; 3 (N methyl 4 oxopiperidinio)propane sulfonate; 8 hydroxyquinoline; 2,2,6,6 tetramethyl 4 piperidone hydrate; N carbethoxy 4 piperidone; tetrahydrothiopyran 4 one,S,S dioxide; and tetrahydrothiopyran- 4-one methonitrate.

12. A concentrated composition especially adapted for bleaching stains on hard surfaces, said composition consisting essentially of:

(a) from about 1% to about 25 by weight of potassium monopersulfate;

(b) from about 0.01% to about 5% by weight of an activator selected from the group consisting of aldehydes, ketones, 1:1 aldehyde bisulfite adducts, 1:1 ketonc bisulfite adducts and hydroxyquinoline compounds, said activator producing a Relative Oxidation Constant of 25 or greater;

(c) from about 1% to about 85% by weight of a buffering agent capable of maintaining the pH of an aqueous solution containing said peroxygen bleaching agent and said activator within the range of from about 7 to 12; and

(d) from about 0.5% to about 70% by weight of a water-soluble halide selected from the group consisting of chloride and bromide salts of sodium, potassium, calcium and magnesium.

13. A hard-surface bleaching composition in accordance with Claim 12 wherein:

(a) the activator is selected from the group consisting of di-2-pyridyl ketone; 1,1-dimethyl-4-oxopiperidinium nitrate; 8-hydroxyquinoline; 1-benzyl-4-piperidone methonitrate; 1-benzyl-4-piperidone methochloride; 3 (N methyl-4-oxopiperidinio) propane sulfonate; 2,2,6,6 tetramethyl-4-piperidonehydrate; N carbethoxy-4-piperidone; tetrahydrothiopyran-4- one,SS-dioxide; and tetrahydrothiopyran-4one methonitrate, and

(b) the water-soluble halide is selected from the group consisting of sodium chloride and sodium bromide, and is present to the extent of from about 1.0% to about 50% by weight.

14. A method for bleaching hard surfaces consisting essentially of contacting said hard surfaces with an aqueous solution consisting essentially of:

(a) a potassium monopersulfate bleaching agent present in an amount sufiicient to provide from about 200 p.p.m. to about 2000 p.p.m. available oxygen in solution;

(b) an activator selected from the group consisting of di-2-pyridyl ketone; l,1-dimethyl-4-oxopiperidinium nitrate; 1-benzyl-4-piperidone methonitrate; l-benzyl- 4-piperidone methochloride; 8-hydroxyquinoline; 3- (N-methyl 4 oxopiperidinio)-propane sulfonate; 2,2,6,6 tetramethyl-4-piperidonehydrate; N-carbet-hoxy 4-piperidone; tetrahydrothiopyran-4-one,'S,S-dioxide; and tetrahydrothiopyran-4-one methonitrate, present in an amount sufficient to provide from about p.p.m. to about 2000 p.p.m. activator in solution;

(c) a water-soluble halide selected from the group consisting of chloride and bromide salts of sodium, potassium, calcium and magnesium present in an amount suflicient to provide from about 1000 p.p.m. to about 50,0000 p.p.m. theoretical halide ion in solution; and

(d) a buflering agent capable of maintaining the pH of said aqueous solution within the range of from about 8 to 12.

15. A composition in accordance with Claim 3 especially adapted for inhibiting laundering solution dye transfer wherein:

(a) the peroxygen bleaching agent is potassium monopersulfate and is present to the extent of from about 1% to about 50% by weight; and

(b) the activator is present to the extent of from about 0.04% to about 65% by weight.

16. A dye transfer inhibition composition in accordance with Claim 15 wherein the activator produces a Relative Oxidation Constant of 5.0 or greater.

17. A dye transfer inhibition composition in accordance with Claim 16 wherein the activator is selected from the group consisting of di-Z-pyridyl ketone; di-2-pyridyl ketone, N-oxide; p-nitroacetophenone; m-nitroacetophenone; p-diacetylbenzene; cyclohexanone; methyl pyruvate; 8-hydroxyquinoline; 8-hydroxyquinoline N-oxide; 2- acetylquinoxaline; 2-acetyl-3-methylquinoxaline; 2-acetylpyridine; 3-acetylpyridine, N-oxide; 4 acetylpyridine-N-oxide; 3-trimethylacetophenone nitrate; 4-trimethylammonioacetophenone nitrate; tetrahydrothiopyran-4-one-S,S-dioxide; N-methyl-p-morphoh'noacetophenone nitrate; 1-methyl-4- piperidone methonitrate; 1-benzyl-4-piperidone methonitrate; 1 benzyl-4-piperidone methochloride; 5-diethyl methylammonio-Z-pentanone nitrate and S-benzyldiethylammonio-Z-pentanone nitrate.

18. A method for inhibiting dye transfer within a laundering solution, said method consisting essentially of adding to said solution:

(a) a potassium monopersulfate peroxygen bleaching agent in an amount suflicient to provide from about 2.5 p.p.m. to about 50 p.p.m. available oxygen in laundering solution;

(-b) an activator selected from the group consisting of di-Z-pyridyl ketone; di-2-pyridyl ketone, N-oxide; pnitroacetophenone; m-nitroacetophenone; p-diacetyl- 'benzene; cyclohexanone; methyl pyruvate; 8-hydroxyquinoline; 8 hydroxyquinoline, N-oxide; 2-acetylquinoxaline; 2-acetyl-3-methylquinoxaline; 2-acetylpyridine; 3-acetylpyridine-N-oxide; 4-acetylpyridine- N-oxide; 3-trimethylacetophenone nitrate; 4-trimethylammonioacetophenone nitrate; tetrahydrothio-pyran-4-one-S,S-dioxide; N-methyl-p-morpholinioacetophenone nitrate; 1-methy1-4-piperidone methonitrate; 1 benzyl-4-piperidone methonitrate; 1-benzyl-4-piperidone methochloride; 5-diethylmethylammonio-2- pentanone nitrate and 5 benzyldiethylammonio-Z- pentanone nitrate, present in an amount sufiicient to provide from about 0.1 p.p.m. to about 500 p.p.m. activator in said laundering solutions; and

(c) a buffering agent capable of maintaining the pH of said laundering solution within the range of from about 8 to 10.

19. A process for activating peroxygen bleaching agents consisting essentially of conjointly dissolving in aqueous solution effective amounts of:

(a) a peroxygen bleaching agent selected from the group consisting of (i) organic peroxyacids having the general formula wherein R is selected from the group consisting of alkylene groups containing from about one to about 16 carbon atoms and arylene groups containing from 6 to about 8 carbon atoms and Y is selected from the group consisting of hydrogen, halogen, alkyl, aryl II I and (ii) water-soluble salts of said peroxy acids;

(b) an activator selected from the group consisting of aldehydes and ketones, said activator producing a Relative Oxidation Constant of 25.0 or greater; and

(c) a buffering agent to maintain the pH of said aqueous solution within the range of from about 7 to 12.

20. A process in accordance with Claim 19:

(a) wherein the bleaching agent is selected from the group consisting of diperadipic acid, diperazelaic acid, diperoxyisophthalic acid, sodium diperoxyisophthalate and potassium diperazelate and is present in an amount sufl'icient to provide from about 2 p.p.m. to 2000 p.p.m. available oxygen in aqueous solution;

(b) wherein the activator is present in an amount sufficient to provide from about 0.1 p.p.m. to about 10,000 p.p.m. of activator in aqueous solution; and

(0) wherein the buffering agent maintains the pH of said aqueous solution within the range of from about 8 to 10.

21. A concentrated peroxygen bleach-containing composition consisting essentially of:

(a) from about 1 to about 75% by weight of a peroxygen bleaching agent selected from the group consisting of (i) organic peroxyacids having the general formula wherein R is selected from the group consisting of alkylene groups containing from about one to about 16 carbon atoms and arylene groups containing from 6 to about 8 carbon atoms and Y is selected from the group consisting of hydrogen, halogen, alkyl, aryl,

and (ii) water-soluble salts of said peroxy acids;

(b) from about 0.01% to about 75 by weight of an activator selected from the group consisting of aldehydes, ketones, 1:1 aldehyde bisulfite adducts, 1:1 ketone bisulfite adducts and hydroxyquinoline compounds, said activator producing a Relative Oxidation Constant of 25 .0 or greater; and

(c) from about 1% to about by weight of a buffering agent capable of maintaining the pH of an aqueous solution containing said peroxygen bleaching agent and said activator within the range of from about 7 to 12.

22. A composition in accordance with claim 21 especially adapted for bleaching stains on fabrics wherein:

(a) the peroxygen bleaching agent is selected from the group consisting of diperazelaic acid and diperoxyisophthalic acid and is present to the extent of from about 5% to about 75 by weight;

(b) the activator is present to the extent of from about 5% to 75% by weight; and

(c) the buffering agent is capable of maintaining aqueous bleaching solution pH Within the range of from about 7 to 10.

23. A fabric-bleaching composition in accordance with Claim 22 wherein the activator is selected from the group consisting of methyl 4-oxo-cyclohexane carboxylate and 1,4-cyclohexanedione.

24. A concentrated composition especially adapted for bleaching stains on fabrics, said composition consisting essentially of:

(a) from about 5% to about 75 by weight of a peroxygen bleaching agent selected from the group consisting of diperazelaic acid and diperoxyisophthalic acid;

(b) from about 0.2% to about 40% by weight of an activator selected from the group consisting of aldehydes, ketones, 1:1 aldehyde bisulfite adducts, 1:1 ketone bisulfite adducts and hydroxyquinoline compounds, said activator having a Relative Oxidation Constant of 25.0 or greater;

(c) from about 1% to about 85% by weight of a buffering agent capable of maintaining the pH of an aqueous solution containing said peroxygen bleaching agent and said activator within the range of from about 7 to 10; and

(d) from about 1% to about 50% by weight of a water-soluble chloride selected from the group consisting of sodium chloride, potassium chloride, calcium chloride and magnesium chloride.

25. A fabric-bleach composition in accordance with Claim 24 wherein:

(a) the activator is selected from the group consisting of di-Z-pyridyl ketone; tetrahydrothiopyran-4-one,S, S-dioxide; chloral hydrate; 1-methyl-4-piperidone oxide, 3 (N-methyl 4-oxopiperidino)propane sulfonate; tropinone methonitrate; tetrahydrothiopyran-4- one methonitrate; 1 benzyl-4-piperidone methonitrate; and 1,1 dimethyl-4-oxopiperidinium nitrate; and

(b) the water-soluble chloride is selected from the group consisting of sodium chloride, potassium chloride, calcium chloride and magnesium chloride, and is present to the extent of from about 4% to about 40% by weight.

26. A method for bleaching fabrics consisting essentially of contacting said fabrics with an aqueous solution consisting essentially of:

(a) peroxygen bleaching agent selected from the group consisting of diperazelaic acid and diperoxyisophthalic acid present in an amount suflicient to provide from about p.p.m. to about 100 p.p.m. available oxygen in solution;

(b) an activator selected from the group consisting of di-Z-pyridyl ketone; tetrahydrothiopyran 4-one,S,S- dioxide; chloral hydrate; 1-rnethyl-4-piperidone oxide, 3-(N-methyl-4-oxopiperidino)-propane sulfonate; tropinone methonitrate; tetrahydrothiopyran 4 one methonitrate; l-benzyl 4 piperidone methonitrate; and 1,1-dimethyl-4-oxopiperidinium nitrate, present in an amount sufiicient to provide from about 10 p.p.m. to about 200 p.p.m. activator in solution;

(c) a water-soluble chloride selected from the group consisting of sodium chloride, potassium chloride, calcium chloride and magnesium chloride present in an amount suificient to provide from about 50 p.p.m. to 1000 p.p.m. theoretical chloride ion in solution; and

(d) a buffering agent capable of maintaining the pH of said aqueous solution within the range of from about 7 to 10.

27. A composition in accordance with Claim 21 especially adapted for bleaching stains on hard surfaces wherein:

(a) the peroxygen bleaching agent is selected from the group consisting of diperazelaic acid and diperoxyisophthalic acid and is present to the extent of from about 1% to about 25% by weight; and (b) the activator is present to the extent of from about 0.01% to about 5% by weight.

28. A hard-surface bleaching composition in accordance with Claim 27 wherein the activator is selected from the group consisting of 1,1-dimethyl-4-oxopiperidinium nitrate; 1-benzyl-4-piperidone methonitrate; di-Z-pyridyl ketone; 1-benzy1-4-piperidone methochloride; 3-(N-methyl 4 oxopiperidino)propane sulfonate; 8 hydroxyquinoline; 2,2,6,6-tetramethyl 4 piperidonehydrate; N- carbethoxy-4-piperidone; tetrahydrothiopyran 4-one,S,S- dioxide; and tetrahydrothiopyran-4-one methonitrate.

29. A concentrated composition especially adapted for bleaching stains on hard surfaces, said composition consisting essentially of:

(a) from about 1% to about 25% by weight of a peroxygen bleaching agent selected from the group consisting of diperazelaic acid and diperoxyisophthalic acid;

(b) from about 0.01% to about 5% by weight of an activator selected from the group consisting of aldehydes, ketones, 1:1 aldehyde bisulfite adducts, 1:1 ketone bisulfite adducts and hydroxyquinoline compounds, said activator producing a Relative Oxidation Constant of 25.0 or greater;

(0) from about 1% to about 85% by weight of a buffering agent capable of maintaining the pH of an aqueous solution containing said peroxy'gen bleaching agent and said activator within the range of from about 7 to 12; and

(d) from about 0.5% to about 70% by weight of a water-soluble halide selected from the group consisting of chloride and bromide salts of sodium, potassium, calcium and magnesium.

30. A hard-surface bleaching composition in accordance with Claim 29 wherein:

(a) the activator is selected from the group consisting of di-Z-pyridyl ketone; 1,1-dimethyl-4-oxopiperidinium nitrate; 1-benzyl-4-piperidone methonitrate; 1- benzyl-4-piperidone methochloride; 8-hydroxyquinoline; 3-(N-methyl 4-oxopiperidino)-propane sulfonate; 2,2,6,6-tetramethyl 4 piperidonehydrate; N- carbethoxy-4-piperidone; tetrahydrothiopyrant-one, S,S-dioxide; and tetrahydrothiopyran 4-one methonitrate; and

(b) the water-soluble halide is selected from the group consisting of sodium chloride and sodium bromide.

3 1. A method for bleaching hard surfaces consisting essentially of contacting said hard surfaces with an aqueous solution consisting essentially of:

(a) a peroxygen bleaching agent selected from the group consisting of diperazelaic acid and diperoxyisophthalic acid present in an amount sufficient to provide from about 200 p.p.m. to about 2000 p.p.m. available oxygen in solution;

(b) an activator selected from the group consisting of di-2-pyridyl ketone; 1,1-dimethyl-4-oxopiperidinium nitrate; 1-benzyl-4-piperidone methonitrate; lbenzyl-4-piperidone methochloride; 8-hydroxyquinoline; 3-(N-methyl 4 oxopiperidino)-propane sulfonate; 2,2,6,6 tetramethyl-4-piperidonehydrate; N-carbethoxy-4-piperidone; tetrahydrothiopyran-4-one,S,S-dioxide; and tetrahydrothiopyran 4 one methonitrate, present in an amount sufiicient to provide from about p.p.m. to about 2000 p.p.m. activator in solution;

(c) a water-soluble halide selected from the group consisting of chloride and bromide salts of sodium, p0- tassium, calcium and magnesium present in an amount sufiicient to provide from about 1000 p.p.m. to about 50,000 p.p.m. theoretical halide ion in solution; and

(d) a buiiering agent capable of maintaining the pH of said aqueous solution within the range of from about 7 to 11.

32. A composition in accordance with Claim 21, especially adapted for inhibiting laundering solution dye transfer wherein:

(a) the peroxygen bleaching agent is diperoxyisophthalic acid and is present to the extent of from about 1% to about 50% by weight; and

(b) the activator is present to the extent of from about 0.04% to about 65% by weight.

33. A dye transfer inhibition composition in accordance with Claim 31 wherein the activator is selected from the group consisting of di-2-pyridyl ketone; di-2-pyridyl ketone, N-oxide, S-hydroxyquinoline; Z-acetylquinoxaline; tetrahydrothiopyran-4-one-S,S-dioxide; l-methyl-4-piperidone methonitrate; l-benzyl-4-piperidone methonitrate; and l-benzyl-4-piperidone methochloride.

34. A method for inhibiting dye transfer within a laundering solution, said method consisting essentially of adding to said solution:

(a) a diperoxyisophthalic acid peroxygen bleaching agent in an amount sufiicient to provide from about 2.5 p.p.m. to about 50 p.p.m. available oxygen in laundering solution;

(b) an activator selected from the group consisting of di-Z-pyridyl ketone; di-Z-pyridyl ketone, N-oxide; 8 hydroxyquinoline; Z-acetylquinoxaline; tetrahydrothiopyran-4-one-S,S-dioxide; 1 methyl-4-piperidone methonitrate; l-benzyl 4 piperidone methonitrate; and 1-benzyl-4-piperidone methochloride, present in an amount sufficient to provide from about 0.1 p.p.m. to about 500 p.p.m. activator in said laundering solutions; and

(c) a buffering agent capable of maintaining the pH of said laundering solution within the range of from about 7 to 10.

References Cited UNITED STATES PATENTS 1,940,768 12/1933 Popkin 8-111 MAYER WEINBLATT, Primary Examiner US. Cl. X.R. 

